Skip to content

dssiaudio

Processes audio through a LADSPA or DSSI plugin instance.

These opcodes require the optional dssi4cs module on Linux. See DSSI and LADSPA plugins for build requirements and setup.

Syntax

aout1 [, aout2, ..., aout9] = dssiaudio(ihandle [, ain1, ain2, ..., ain9])

aout1 [, aout2, ..., aout9] dssiaudio ihandle [, ain1, ain2, ..., ain9]

Initialization

ihandle is the instance handle returned by dssiinit. Use the same ksmps as the code that loaded the instance.

Performance

ain1 through ain9 supply audio input channels. aout1 through aout9 receive audio output channels. The opcode supports up to nine inputs and nine outputs.

Channels follow the order of the plugin's audio input ports and audio output ports, with control ports skipped. Supply every audio input and request no more outputs than the plugin provides. A plugin with no audio inputs takes only ihandle.

Call dssiactivate with 1 before processing. While active, dssiaudio calls the plugin's LADSPA run function once per control cycle. While inactive, it outputs zeros and does not run the plugin.

Input samples are divided by 0dbfs before they reach the plugin. Output samples are multiplied by 0dbfs on return. Control values do not receive this scaling.

Use one dssiaudio call per handle per control cycle. To process independent signals, load separate instances. DSSI synth-event processing is not part of this opcode.

Examples

The example passes a sine tone through the SDK mono amplifier at half gain. It sets the control and activates the plugin before processing. It requires amp.so and the Linux setup.

dssiaudio example
 1
 2
 3
 4
 5
 6
 7
 8
 9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
<CsoundSynthesizer>
<CsOptions>
-odac -d
</CsOptions>
<CsInstruments>
sr = 48000
ksmps = 32
nchnls = 2
0dbfs = 1

giHandle = dssiinit("/usr/lib/ladspa/amp.so", 0, 1)

instr 1
  dssictls(giHandle, 0, 0.5, 1)
  dssiactivate(giHandle, 1)
  aInput = oscili(0.1, 440)
  aOutput = dssiaudio(giHandle, aInput)
  out(aOutput, aOutput)
endin
</CsInstruments>
<CsScore>
i 1 0 6
e
</CsScore>
</CsoundSynthesizer>

See also

dssiinit, dssiactivate, dssictls, dssiaudio, dssilist, DSSI and LADSPA plugins

Credits

Author Andres Cabrera, 2005. Uses code from Richard Furse's LADSPA SDK.